How to Get Rid of Gunk From a Gas Tank

by Erin Stewart

As gas ages, it has the potential to varnish, or thicken up and turn solid. If you have a gas tank with old gas, you will need to get rid of the gunk from the gas tank before you run the vehicle. If you have a gas tank that has been sitting empty for an extended period of time, it could have rust in it and will also need to be cleaned. And in the event that someone puts a foreign substance or object in your gas tank, you will also need to clean it before you operate your vehicle.

Remove the gas tank from the vehicle.

Take the gas tank to a radiator shop and have it flushed. This is the most effective option.

Professionals at a radiator shop will dip the gas tank in chemicals, flush out any varnish and put a new coating on the inside of the gas tank. They can also use acid to remove rust.

To get rid of gunk in a gas tank yourself, purchase a gas tank cleaner kit at any local auto parts store. Gas tank cleaner kits contain acid that is supposed to eat away varnish and rust.

Follow the directions that come with the kit. Most gas tank cleaner kits require you to put a chain or rocks in the gas tank, add the acid and then vigorously shake the gas tank to get rid of the gunk. These kits also come with a new coating for the inside of the gas tank.


  • check You can often order a replacement gas tank for the price of getting one cleaned. If you have a plastic gas tank, the chemicals used to eat the varnish may also eat the plastic.


  • close Cutting the gas tank open to get it clean is dangerous. Gas fumes and varnish are highly flammable and could catch on fire. If you are sensitive to gas fumes, wear a mask or respirator.

Items you will need

About the Author

Erin Stewart is a professional editor and copywriter who has served as a newspaper reporter, designer, and news editor, and currently works as part of a dynamic marketing communications team. Erin has a Bachelor of Arts degree in English with an editing minor from Brigham Young University in Provo, Utah.

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